Research On Profile Modification Technology Of Precision Cycloidal Transmission Based On Tooth Profile Segmentation

Precise transmission is a kind of mechanical transmission with high precision to transmit motion and power.It is one of the key functional components in professional manufacturing and equipment industries,aerospace industries and national defense industries.Cycloid transmission has the characteristics of strong loading capacity,small inertia moment,good transmission stability,Rigid transmission and small backlash.In recent years,it has been more and more widely used in the field of precision transmission.The cycloid gear tooth profile,as the direct action surface to bear load and transmit power,is an important factor affecting the performance of cycloid transmission.Therefore,systematically study the modification of cycloidal tooth profile in precision cycloidal transmission,improve the transmission accuracy,transmission efficiency and the working life of precision cycloidal transmission are of great theoretical significance and engineering significance to promote the research and development of precision reducer,production and application,and the development of precision industrial robot industry in China.The main research content of this paper are as follows:[1].Study the geometric characteristics of cycloid,study its curvature,pressure angle and other characteristics,then establish the contact force model between cycloid and needle wheel in meshing process,discuss the disadvantage of generating cutting and the advancement of forming cutting,and lead to the goal of modern modification exploration is that the ideal tooth profile curve can be applied in engineering practice.[2].Through the actual disassembly of the prototype of Nabtesco RV reducer,the precise measurement of cycloidal wheel in the prototype and the investigation to the RV reducer manufacturer,and according to my own research,the modification target of precise cycloidal transmission is obtained.On this basis,a new modification method of precise cycloidal pinwheel transmission based on tooth profile segmentation is proposed.According to the principle of optimum force transmission,the cycloidal tooth profile is divided into main meshing working section,root non-working section and top non-working section.The main meshing working section maintains the original theoretical tooth profile,the non-working section of the tooth root considers the amount of lubricating grease to be stored for elastohydrodynamic lubrication to determine the modification amount,and the non-working section of the tooth top considers errors such as manufacturing and assembly to determine the modification amount.After determining the modification amount,the profile of non-working segment is fitted by high-order spline curve,so that it can transition smoothly with high-order of working segment,and the second-order transition is maintained at the junction of root and top of tooth.[3].Under the actual lubrication conditions,judge the lubrication state of the modified cycloidal transmission in the meshing process,and calculate the sliding friction coefficient,so as to calculate and verify the meshing transmission efficiency of the modified cycloidal pinwheel transmission,and to verify the theoretical feasibility of the modified method compared with the existing research.[4].Obtain the stress-strain and deformation distribution of the modified cycloidal gear profile during meshing process by Ansys Workbench finite element analysis,and verify the meshing condition,transmission stability and of the modified cycloidal transmission.The prototype was trial-produced and the meshing rigidity test device was designed.